bisecting fixing commit since cbfa1702aaf69b2311ea1b35e04f113c48368c67 building syzkaller on 5abc3f1ab298244473b613c289f1536e366fcf04 testing commit cbfa1702aaf69b2311ea1b35e04f113c48368c67 with gcc (GCC) 8.4.1 20210217 kernel signature: 2a1750951f7b443e6dcc26507f73c561c4d9ebc2d992f9837e4de74387bc1ce1 run #0: crashed: KASAN: use-after-free Read in diFree run #1: crashed: KASAN: use-after-free Read in diFree run #2: crashed: general protection fault in diFree run #3: crashed: general protection fault in diFree run #4: crashed: KASAN: use-after-free Read in diFree run #5: crashed: KASAN: use-after-free Read in diFree run #6: crashed: KASAN: use-after-free Read in diFree run #7: crashed: KASAN: use-after-free Read in diFree run #8: crashed: general protection fault in diFree run #9: crashed: general protection fault in diFree run #10: crashed: general protection fault in diFree run #11: crashed: general protection fault in diFree run #12: crashed: KASAN: use-after-free Read in diFree run #13: crashed: general protection fault in diFree run #14: crashed: KASAN: use-after-free Read in diFree run #15: crashed: general protection fault in diFree run #16: crashed: KASAN: use-after-free Read in diFree run #17: crashed: general protection fault in diFree run #18: crashed: KASAN: use-after-free Read in diFree run #19: crashed: general protection fault in diFree testing current HEAD 7d7d1c0ab3eb7c8d8f63a126535018007823b207 testing commit 7d7d1c0ab3eb7c8d8f63a126535018007823b207 with gcc (GCC) 8.4.1 20210217 kernel signature: b619016049639766c07b4c05921b76fb4d2c88b10d27b8e07404729366760a56 run #0: crashed: general protection fault in diFree run #1: crashed: KASAN: use-after-free Read in diFree run #2: crashed: KASAN: use-after-free Read in diFree run #3: crashed: general protection fault in diFree run #4: crashed: KASAN: use-after-free Read in diFree run #5: crashed: KASAN: use-after-free Read in diFree run #6: crashed: KASAN: use-after-free Read in diFree run #7: crashed: general protection fault in diFree run #8: crashed: KASAN: use-after-free Read in diFree run #9: crashed: KASAN: use-after-free Read in diFree revisions tested: 2, total time: 28m46.263796463s (build: 21m28.949450703s, test: 6m41.113470072s) the crash still happens on HEAD commit msg: Linux 4.14.232 crash: KASAN: use-after-free Read in diFree ERROR: (device loop4): xtSearch: XT_GETPAGE: xtree page corrupt ERROR: (device loop2): xtSearch: XT_GETPAGE: xtree page corrupt ERROR: (device loop3): xtSearch: XT_GETPAGE: xtree page corrupt ================================================================== BUG: KASAN: use-after-free in diFree+0x153c/0x32a0 fs/jfs/jfs_imap.c:892 Read of size 4 at addr ffff8881c39b5804 by task syz-executor.1/8160 CPU: 0 PID: 8160 Comm: syz-executor.1 Not tainted 4.14.232-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x14b/0x1e7 lib/dump_stack.c:58 print_address_description.cold.6+0x9/0x1ca mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report mm/kasan/report.c:409 [inline] kasan_report.cold.7+0x11a/0x2d3 mm/kasan/report.c:393 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:429 diFree+0x153c/0x32a0 fs/jfs/jfs_imap.c:892 jfs_evict_inode+0xd1/0x110 fs/jfs/inode.c:164 evict+0x29c/0x590 fs/inode.c:555 iput_final fs/inode.c:1524 [inline] iput fs/inode.c:1551 [inline] iput+0x3ac/0x810 fs/inode.c:1536 diFreeSpecial fs/jfs/jfs_imap.c:569 [inline] diFreeSpecial+0x5d/0x80 fs/jfs/jfs_imap.c:561 jfs_umount+0xce/0x300 fs/jfs/jfs_umount.c:78 jfs_fill_super+0x61d/0xaf0 fs/jfs/super.c:633 mount_bdev+0x26f/0x330 fs/super.c:1134 jfs_do_mount+0x10/0x20 fs/jfs/super.c:703 mount_fs+0x7f/0x270 fs/super.c:1237 vfs_kern_mount.part.9+0x58/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x352/0x2af0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xb1/0xd0 fs/namespace.c:3072 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x466baa RSP: 002b:00007f4cd7353fa8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 0000000000466baa RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f4cd7354000 RBP: 00007f4cd7354040 R08: 00007f4cd7354040 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000020000000 R13: 0000000020000100 R14: 00007f4cd7354000 R15: 000000002006d200 Allocated by task 8160: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc.part.1+0x62/0xf0 mm/kasan/kasan.c:551 kasan_kmalloc+0xaf/0xc0 mm/kasan/kasan.c:536 kmem_cache_alloc_trace+0x152/0x3f0 mm/slab.c:3618 kmalloc include/linux/slab.h:488 [inline] diMount+0x4d/0x680 fs/jfs/jfs_imap.c:118 jfs_mount+0x27f/0x340 fs/jfs/jfs_mount.c:191 jfs_fill_super+0x524/0xaf0 fs/jfs/super.c:589 mount_bdev+0x26f/0x330 fs/super.c:1134 jfs_do_mount+0x10/0x20 fs/jfs/super.c:703 mount_fs+0x7f/0x270 fs/super.c:1237 vfs_kern_mount.part.9+0x58/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x352/0x2af0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xb1/0xd0 fs/namespace.c:3072 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 8160: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xab/0x190 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xcc/0x270 mm/slab.c:3815 diUnmount+0xdb/0x120 fs/jfs/jfs_imap.c:210 jfs_umount+0xc6/0x300 fs/jfs/jfs_umount.c:76 jfs_fill_super+0x61d/0xaf0 fs/jfs/super.c:633 mount_bdev+0x26f/0x330 fs/super.c:1134 jfs_do_mount+0x10/0x20 fs/jfs/super.c:703 mount_fs+0x7f/0x270 fs/super.c:1237 vfs_kern_mount.part.9+0x58/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x352/0x2af0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xb1/0xd0 fs/namespace.c:3072 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb The buggy address belongs to the object at ffff8881c39b5800 which belongs to the cache kmalloc-32768 of size 32768 The buggy address is located 4 bytes inside of 32768-byte region [ffff8881c39b5800, ffff8881c39bd800) The buggy address belongs to the page: page:ffffea00070e6c00 count:1 mapcount:0 mapping:ffff8881c39b5800 index:0x0 compound_mapcount: 0 flags: 0x17ffe0000008100(slab|head) raw: 017ffe0000008100 ffff8881c39b5800 0000000000000000 0000000100000001 raw: ffffea00070e6820 ffff8881f6001d48 ffff8881f6002380 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881c39b5700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881c39b5780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8881c39b5800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881c39b5880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881c39b5900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ERROR: (device loop0): xtSearch: XT_GETPAGE: xtree page corrupt imap: ffff8881c39b5800: e870c780 ffff8881 00000000 00000000 ERROR: (device loop5): xtSearch: XT_GETPAGE: xtree page corrupt imap: ffff8881c39b5810: 00000000 00000000 00000000 00000000 ERROR: (device loop1): diFree: inum = 16, iagno = 0, nextiag = -30591 ERROR: (device loop3): xtSearch: XT_GETPAGE: xtree page corrupt ERROR: (device loop2): xtSearch: XT_GETPAGE: xtree page corrupt ERROR: (device loop4): xtSearch: XT_GETPAGE: xtree page corrupt ERROR: (device loop5): xtSearch: XT_GETPAGE: xtree page corrupt imap: ffff8881c7f71a80: 00000000 00000000 00000000 00000000 imap: ffff8881c7d21800: 00000000 00000000 00000000 00000000 ERROR: (device loop0): xtSearch: XT_GETPAGE: xtree page corrupt ERROR: (device loop1): xtSearch: XT_GETPAGE: xtree page corrupt ERROR: (device loop2): xtSearch: XT_GETPAGE: xtree page corrupt ERROR: (device loop4): xtSearch: XT_GETPAGE: xtree page corrupt imap: ffff8881c7f71a90: 00000000 00000000 00000000 00000000 kasan: CONFIG_KASAN_INLINE enabled imap: ffff8881c7d21810: 00000000 00000000 00000000 00000000 kasan: GPF could be caused by NULL-ptr deref or user memory access ERROR: (device loop5): diFree: inum = 16, iagno = 0, nextiag = -30591 kasan: CONFIG_KASAN_INLINE enabled ERROR: (device loop3): diFree: inum = 16, iagno = 0, nextiag = -30591 general protection fault: 0000 [#1] PREEMPT SMP KASAN Modules linked in: CPU: 0 PID: 8212 Comm: syz-executor.1 Tainted: G B 4.14.232-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8881e79920c0 task.stack: ffff8881cdd18000 RIP: 0010:diFree+0x1b5/0x32a0 fs/jfs/jfs_imap.c:892 RSP: 0018:ffff8881cdd1f7a0 EFLAGS: 00010247 RAX: dffffc0000000000 RBX: 0000000000000004 RCX: 1ffff110390328ed RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8881c81943e8 RBP: ffff8881cdd1fa50 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000040 R11: ffff8881e79920c0 R12: ffff8881e6137800 R13: 0000000000000000 R14: ffff8881cdd1fa28 R15: ffff8881c8194468 FS: 00007f4cd7354700(0000) GS:ffff8881f6600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7698729000 CR3: 00000001daff9003 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: jfs_evict_inode+0xd1/0x110 fs/jfs/inode.c:164 evict+0x29c/0x590 fs/inode.c:555 iput_final fs/inode.c:1524 [inline] iput fs/inode.c:1551 [inline] iput+0x3ac/0x810 fs/inode.c:1536 diFreeSpecial fs/jfs/jfs_imap.c:569 [inline] diFreeSpecial+0x5d/0x80 fs/jfs/jfs_imap.c:561 jfs_mount+0x295/0x340 fs/jfs/jfs_mount.c:202 jfs_fill_super+0x524/0xaf0 fs/jfs/super.c:589 mount_bdev+0x26f/0x330 fs/super.c:1134 jfs_do_mount+0x10/0x20 fs/jfs/super.c:703 mount_fs+0x7f/0x270 fs/super.c:1237 vfs_kern_mount.part.9+0x58/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x352/0x2af0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xb1/0xd0 fs/namespace.c:3072 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x466baa RSP: 002b:00007f4cd7353fa8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 0000000000466baa RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f4cd7354000 RBP: 00007f4cd7354040 R08: 00007f4cd7354040 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000020000000 R13: 0000000020000100 R14: 00007f4cd7354000 R15: 000000002006d200 Code: 4c 8b 68 80 48 8b 85 28 fe ff ff 49 8d 5d 04 48 c1 e8 0c 48 89 da 48 c1 ea 03 48 89 85 30 fe ff ff 48 b8 00 00 00 00 00 fc ff df <0f> b6 14 02 48 89 d8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 RIP: diFree+0x1b5/0x32a0 fs/jfs/jfs_imap.c:892 RSP: ffff8881cdd1f7a0 ---[ end trace 1cf63a324fd67cba ]---